<?php
/*
 * Copyright (c) 2003-2012, CKSource - Frederico Knabben. All rights reserved.
 * For licensing, see LICENSE.html or http://ckeditor.com/license
 */

/**
 * \brief CKEditor class that can be used to create editor
 * instances in PHP pages on server side.
 * @see http://ckeditor.com
 *
 * Sample usage:
 * @code
 * $CKEditor = new CKEditor();
 * $CKEditor->editor("editor1", "<p>Initial value.</p>");
 * @endcode
 */
class CKEditor
{
  /**
   * The version of %CKEditor.
   * \private
   */
  var $version = '3.6.3';
  /**
   * A constant string unique for each release of %CKEditor.
   * \private
   */
  var $_timestamp = 'C3HA5RM';

  /**
   * URL to the %CKEditor installation directory (absolute or relative to document root).
   * If not set, CKEditor will try to guess it's path.
   *
   * Example usage:
   * @code
   * $CKEditor->basePath = '/ckeditor/';
   * @endcode
   */
  var $basePath;
  /**
   * An array that holds the global %CKEditor configuration.
   * For the list of available options, see http://docs.cksource.com/ckeditor_api/symbols/CKEDITOR.config.html
   *
   * Example usage:
   * @code
   * $CKEditor->config['height'] = 400;
   * // Use @@ at the beggining of a string to ouput it without surrounding quotes.
   * $CKEditor->config['width'] = '@@screen.width * 0.8';
   * @endcode
   */
  var $config = array();
  /**
   * A boolean variable indicating whether CKEditor has been initialized.
   * Set it to true only if you have already included
   * &lt;script&gt; tag loading ckeditor.js in your website.
   */
  var $initialized = false;
  /**
   * Boolean variable indicating whether created code should be printed out or returned by a function.
   *
   * Example 1: get the code creating %CKEditor instance and print it on a page with the "echo" function.
   * @code
   * $CKEditor = new CKEditor();
   * $CKEditor->returnOutput = true;
   * $code = $CKEditor->editor("editor1", "<p>Initial value.</p>");
   * echo "<p>Editor 1:</p>";
   * echo $code;
   * @endcode
   */
  var $returnOutput = false;
  /**
   * An array with textarea attributes.
   *
   * When %CKEditor is created with the editor() method, a HTML &lt;textarea&gt; element is created,
   * it will be displayed to anyone with JavaScript disabled or with incompatible browser.
   */
  var $textareaAttributes = array( "rows" => 8, "cols" => 60 );
  /**
   * A string indicating the creation date of %CKEditor.
   * Do not change it unless you want to force browsers to not use previously cached version of %CKEditor.
   */
  var $timestamp = "C3HA5RM";
  /**
   * An array that holds event listeners.
   * \private
   */
  var $_events = array();
  /**
   * An array that holds global event listeners.
   * \private
   */
  var $_globalEvents = array();

  /**
   * Main Constructor.
   *
   *  @param $basePath (string) URL to the %CKEditor installation directory (optional).
   */
  function CKEditor($basePath = null) {
    if (!empty($basePath)) {
      $this->basePath = $basePath;
    }
  }

  /**
   * Creates a %CKEditor instance.
   * In incompatible browsers %CKEditor will downgrade to plain HTML &lt;textarea&gt; element.
   *
   * @param $name (string) Name of the %CKEditor instance (this will be also the "name" attribute of textarea element).
   * @param $value (string) Initial value (optional).
   * @param $config (array) The specific configurations to apply to this editor instance (optional).
   * @param $events (array) Event listeners for this editor instance (optional).
   *
   * Example usage:
   * @code
   * $CKEditor = new CKEditor();
   * $CKEditor->editor("field1", "<p>Initial value.</p>");
   * @endcode
   *
   * Advanced example:
   * @code
   * $CKEditor = new CKEditor();
   * $config = array();
   * $config['toolbar'] = array(
   *     array( 'Source', '-', 'Bold', 'Italic', 'Underline', 'Strike' ),
   *     array( 'Image', 'Link', 'Unlink', 'Anchor' )
   * );
   * $events['instanceReady'] = 'function (ev) {
   *     alert("Loaded: " + ev.editor.name);
   * }';
   * $CKEditor->editor("field1", "<p>Initial value.</p>", $config, $events);
   * @endcode
   */
  function editor($name, $value = "", $config = array(), $events = array())
  {
    $attr = "";
    foreach ($this->textareaAttributes as $key => $val) {
      $attr.= " " . $key . '="' . str_replace('"', '&quot;', $val) . '"';
    }
    $out = "<textarea name=\"" . $name . "\"" . $attr . ">" . htmlspecialchars($value) . "</textarea>\n";
    if (!$this->initialized) {
      $out .= $this->init();
    }

    $_config = $this->configSettings($config, $events);

    $js = $this->returnGlobalEvents();
    if (!empty($_config))
    $js .= "CKEDITOR.replace('".$name."', ".$this->jsEncode($_config).");";
    else
    $js .= "CKEDITOR.replace('".$name."');";

    $out .= $this->script($js);

    if (!$this->returnOutput) {
      print $out;
      $out = "";
    }

    return $out;
  }

  /**
   * Replaces a &lt;textarea&gt; with a %CKEditor instance.
   *
   * @param $id (string) The id or name of textarea element.
   * @param $config (array) The specific configurations to apply to this editor instance (optional).
   * @param $events (array) Event listeners for this editor instance (optional).
   *
   * Example 1: adding %CKEditor to &lt;textarea name="article"&gt;&lt;/textarea&gt; element:
   * @code
   * $CKEditor = new CKEditor();
   * $CKEditor->replace("article");
   * @endcode
   */
  function replace($id, $config = array(), $events = array())
  {
    $out = "";
    if (!$this->initialized) {
      $out .= $this->init();
    }

    $_config = $this->configSettings($config, $events);

    $js = $this->returnGlobalEvents();
    if (!empty($_config)) {
      $js .= "CKEDITOR.replace('".$id."', ".$this->jsEncode($_config).");";
    }
    else {
      $js .= "CKEDITOR.replace('".$id."');";
    }
    $out .= $this->script($js);

    if (!$this->returnOutput) {
      print $out;
      $out = "";
    }

    return $out;
  }

  /**
   * Replace all &lt;textarea&gt; elements available in the document with editor instances.
   *
   * @param $className (string) If set, replace all textareas with class className in the page.
   *
   * Example 1: replace all &lt;textarea&gt; elements in the page.
   * @code
   * $CKEditor = new CKEditor();
   * $CKEditor->replaceAll();
   * @endcode
   *
   * Example 2: replace all &lt;textarea class="myClassName"&gt; elements in the page.
   * @code
   * $CKEditor = new CKEditor();
   * $CKEditor->replaceAll( 'myClassName' );
   * @endcode
   */
  function replaceAll($className = null)
  {
    $out = "";
    if (!$this->initialized) {
      $out .= $this->init();
    }

    $_config = $this->configSettings();

    $js = $this->returnGlobalEvents();
    if (empty($_config)) {
      if (empty($className)) {
        $js .= "CKEDITOR.replaceAll();";
      }
      else {
        $js .= "CKEDITOR.replaceAll('".$className."');";
      }
    }
    else {
      $classDetection = "";
      $js .= "CKEDITOR.replaceAll( function(textarea, config) {\n";
      if (!empty($className)) {
        $js .= "	var classRegex = new RegExp('(?:^| )' + '". $className ."' + '(?:$| )');\n";
        $js .= "	if (!classRegex.test(textarea.className))\n";
        $js .= "		return false;\n";
      }
      $js .= "	CKEDITOR.tools.extend(config, ". $this->jsEncode($_config) .", true);";
      $js .= "} );";

    }

    $out .= $this->script($js);

    if (!$this->returnOutput) {
      print $out;
      $out = "";
    }

    return $out;
  }

  /**
   * Adds event listener.
   * Events are fired by %CKEditor in various situations.
   *
   * @param $event (string) Event name.
   * @param $javascriptCode (string) Javascript anonymous function or function name.
   *
   * Example usage:
   * @code
   * $CKEditor->addEventHandler('instanceReady', 'function (ev) {
   *     alert("Loaded: " + ev.editor.name);
   * }');
   * @endcode
   */
  function addEventHandler($event, $javascriptCode)
  {
    if (!isset($this->_events[$event])) {
      $this->_events[$event] = array();
    }
    // Avoid duplicates.
    if (!in_array($javascriptCode, $this->_events[$event])) {
      $this->_events[$event][] = $javascriptCode;
    }
  }

  /**
   * Clear registered event handlers.
   * Note: this function will have no effect on already created editor instances.
   *
   * @param $event (string) Event name, if not set all event handlers will be removed (optional).
   */
  function clearEventHandlers($event = null)
  {
    if (!empty($event)) {
      $this->_events[$event] = array();
    }
    else {
      $this->_events = array();
    }
  }

  /**
   * Adds global event listener.
   *
   * @param $event (string) Event name.
   * @param $javascriptCode (string) Javascript anonymous function or function name.
   *
   * Example usage:
   * @code
   * $CKEditor->addGlobalEventHandler('dialogDefinition', 'function (ev) {
   *     alert("Loading dialog: " + ev.data.name);
   * }');
   * @endcode
   */
  function addGlobalEventHandler($event, $javascriptCode)
  {
    if (!isset($this->_globalEvents[$event])) {
      $this->_globalEvents[$event] = array();
    }
    // Avoid duplicates.
    if (!in_array($javascriptCode, $this->_globalEvents[$event])) {
      $this->_globalEvents[$event][] = $javascriptCode;
    }
  }

  /**
   * Clear registered global event handlers.
   * Note: this function will have no effect if the event handler has been already printed/returned.
   *
   * @param $event (string) Event name, if not set all event handlers will be removed (optional).
   */
  function clearGlobalEventHandlers($event = null)
  {
    if (!empty($event)) {
      $this->_globalEvents[$event] = array();
    }
    else {
      $this->_globalEvents = array();
    }
  }

  /**
   * Prints javascript code.
   * \private
   *
   * @param string $js
   */
  function script($js)
  {
    $out = "<script type=\"text/javascript\">";
    $out .= "//<![CDATA[\n";
    $out .= $js;
    $out .= "\n//]]>";
    $out .= "</script>\n";

    return $out;
  }

  /**
   * Returns the configuration array (global and instance specific settings are merged into one array).
   * \private
   *
   * @param $config (array) The specific configurations to apply to editor instance.
   * @param $events (array) Event listeners for editor instance.
   */
  function configSettings($config = array(), $events = array())
  {
    $_config = $this->config;
    $_events = $this->_events;

    if (is_array($config) && !empty($config)) {
      $_config = array_merge($_config, $config);
    }

    if (is_array($events) && !empty($events)) {
      foreach ($events as $eventName => $code) {
        if (!isset($_events[$eventName])) {
          $_events[$eventName] = array();
        }
        if (!in_array($code, $_events[$eventName])) {
          $_events[$eventName][] = $code;
        }
      }
    }

    if (!empty($_events)) {
      foreach($_events as $eventName => $handlers) {
        if (empty($handlers)) {
          continue;
        }
        else if (count($handlers) == 1) {
          $_config['on'][$eventName] = '@@'.$handlers[0];
        }
        else {
          $_config['on'][$eventName] = '@@function (ev){';
          foreach ($handlers as $handler => $code) {
            $_config['on'][$eventName] .= '('.$code.')(ev);';
          }
          $_config['on'][$eventName] .= '}';
        }
      }
    }

    return $_config;
  }

  /**
   * Return global event handlers.
   * \private
   */
  function returnGlobalEvents()
  {
    static $returnedEvents;
    $out = "";

    if (!isset($returnedEvents)) {
      $returnedEvents = array();
    }

    if (!empty($this->_globalEvents)) {
      foreach ($this->_globalEvents as $eventName => $handlers) {
        foreach ($handlers as $handler => $code) {
          if (!isset($returnedEvents[$eventName])) {
            $returnedEvents[$eventName] = array();
          }
          // Return only new events
          if (!in_array($code, $returnedEvents[$eventName])) {
            $out .= ($code ? "\n" : "") . "CKEDITOR.on('". $eventName ."', $code);";
            $returnedEvents[$eventName][] = $code;
          }
        }
      }
    }

    return $out;
  }

  /**
   * Initializes CKEditor (executed only once).
   * \private
   */
  function init()
  {
    static $initComplete;
    $out = "";

    if (!empty($initComplete)) {
      return "";
    }

    if ($this->initialized) {
      $initComplete = true;
      return "";
    }

    $args = "";
    $ckeditorPath = $this->ckeditorPath();

    if (!empty($this->timestamp) && $this->timestamp != "%"."TIMESTAMP%") {
      $args = '?t=' . $this->timestamp;
    }

    // Skip relative paths...
    if (strpos($ckeditorPath, '..') !== 0) {
      $out .= $this->script("window.CKEDITOR_BASEPATH='". $ckeditorPath ."';");
    }

    $out .= "<script type=\"text/javascript\" src=\"" . $ckeditorPath . 'ckeditor.js' . $args . "\"></script>\n";

    $extraCode = "";
    if ($this->timestamp != $this->_timestamp) {
      $extraCode .= ($extraCode ? "\n" : "") . "CKEDITOR.timestamp = '". $this->timestamp ."';";
    }
    if ($extraCode) {
      $out .= $this->script($extraCode);
    }

    $initComplete = $this->initialized = true;

    return $out;
  }

  /**
   * Return path to ckeditor.js.
   * \private
   */
  function ckeditorPath()
  {
    if (!empty($this->basePath)) {
      return $this->basePath;
    }

    /**
     * The absolute pathname of the currently executing script.
     * Note: If a script is executed with the CLI, as a relative path, such as file.php or ../file.php,
     * $_SERVER['SCRIPT_FILENAME'] will contain the relative path specified by the user.
     */
    if (isset($_SERVER['SCRIPT_FILENAME'])) {
      $realPath = dirname($_SERVER['SCRIPT_FILENAME']);
    }
    else {
      /**
       * realpath - Returns canonicalized absolute pathname
       */
      $realPath = realpath( './' ) ;
    }

    /**
     * The filename of the currently executing script, relative to the document root.
     * For instance, $_SERVER['PHP_SELF'] in a script at the address http://example.com/test.php/foo.bar
     * would be /test.php/foo.bar.
     */
    $selfPath = dirname($_SERVER['PHP_SELF']);
    $file = str_replace("\\", "/", __FILE__);

    if (!$selfPath || !$realPath || !$file) {
      return "/ckeditor/";
    }

    $documentRoot = substr($realPath, 0, strlen($realPath) - strlen($selfPath));
    $fileUrl = substr($file, strlen($documentRoot));
    $ckeditorUrl = str_replace("ckeditor_php4.php", "", $fileUrl);

    return $ckeditorUrl;
  }

  /**
   * This little function provides a basic JSON support.
   * \private
   *
   * @param mixed $val
   * @return string
   */
  function jsEncode($val)
  {
    if (is_null($val)) {
      return 'null';
    }
    if (is_bool($val)) {
      return $val ? 'true' : 'false';
    }
    if (is_int($val)) {
      return $val;
    }
    if (is_float($val)) {
      return str_replace(',', '.', $val);
    }
    if (is_array($val) || is_object($val)) {
      if (is_array($val) && (array_keys($val) === range(0,count($val)-1))) {
        return '[' . implode(',', array_map(array($this, 'jsEncode'), $val)) . ']';
      }
      $temp = array();
      foreach ($val as $k => $v){
        $temp[] = $this->jsEncode("{$k}") . ':' . $this->jsEncode($v);
      }
      return '{' . implode(',', $temp) . '}';
    }
    // String otherwise
    if (strpos($val, '@@') === 0)
    return substr($val, 2);
    if (strtoupper(substr($val, 0, 9)) == 'CKEDITOR.')
    return $val;

    return '"' . str_replace(array("\\", "/", "\n", "\t", "\r", "\x08", "\x0c", '"'), array('\\\\', '\\/', '\\n', '\\t', '\\r', '\\b', '\\f', '\"'), $val) . '"';
  }
}
